I would hope not , if you reach out to Arianna she may make an exception and have you come to the reception but please reach out to her. Do not just show up without an invitation or with talking to the wedding party .
There will be food provided but feel free to bring food to share as well. Never turn down good food ! You may eat before you come it is your decision
Wear shoes that are sensible , we are in a field.
Dress how you would like , we will have a heated tent if it is too cold. There will be a fire if it is not too windy. There will be blankets for the people that are cold as well.